[Open-graphics] USB interface on the logic/bus-analyzer

[Dieter]

> What about one of FTDI's USB - FIFO converters? (or USB-UART)
> the FIFO ones have
> "Data transfer rate to 1 Megabyte / second - D2XX Direct Drivers."
> or
> "Data transfer rate to 300 kilobyte / second - VCP Drivers."
> I am not quite sure what D2XX or VCP means, but you can get D2XX for  
> Mac OS X, Linux, etc.

VCP = Virtual COM Port driver
D2XX drivers allow direct access to the USB device through a DLL.
(No, they don't seem to explain what a "DLL" is.)

The good news is that there are drivers for FreeBSD, OpenBSD, QNC, Linux
and OS-X (depending on exactly which OS release you are running and exactly
which device).  Haven't found anything on drivers for NetBSD, Solaris, or Plan 9.
I don't see a transfer rate listed for the various OSes.  (1 MB/s vs 300 KB/s)

"Entire USB protocol handled on the chip - No USB-specific firmware programming required."

"Simple interface to MCU / PLD / FPGA logic with simple 4-wire handshake interface."

"Fully integrated clock - no external crystal, oscillator, or resonator required."

Some of the evaluation kits look promising, a DIP type "package" with USB connector.
http://www.ftdichip.com/Products/FTEvaluationKits.htm

Haven't seen prices yet...

> There is also a so-called "USB to UART Switch" manufactured by Dallas/ 
> Maxim Semiconductors
> that can switch the two signals - this would be useful for having  
> both, but just USB would probably work.

switch the two signals?  You lost me there.